Aim to do it 3x in a row (~30 minutes). When I started I was barely able to do a single set, then once 1 set was too little I was ramping up intensity more and more (like to 60 pushups per 30 seconds), then added one more run etc. Now I do the first one as a warm up (knees etc.) and second/third run are getting progressively more crazy. It helped me going from nerdy to very athletic in 2 years. Also, combine with up to 100 decline wide pushups for chest improvement; in 2 months you'll see massive improvements. Then of course good diet, sleep, etc. I actually start my day with it; 6am wake up, some drink/hygiene, then 6:15 HIIT with 7-minute workout sets, 6:45 breakfast, 7:00 work (from home), 3pm end of work and fun begins.